Agata Filip

Circulating microenvironment of CLL: are nurse-like cells related to tumor-associated macrophages?

B-cell chronic lymphocytic leukemia (B-CLL) is one of the most common hematologic malignancies in Western countries. Accumulation of leukemic lymphocytes in peripheral blood, bone marrow and secondary lymphatic organs of CLL patients is due to decreased apoptosis rather than to increased proliferation. The former is driven by signals from a specific microenvironment, created by stromal cells of mesenchymal origin, follicular dendritic cells, T lymphocytes and others. Nurse-like cells (NLCs) were first described to differentiate from peripheral blood mononuclear cells of CLL patients in vitro, then they have been also found in proliferation centers of their lymphatic tissues. Like tumor-associated macrophages (TAMs) in solid tumors, nurse-like cells promote survival of CLL lymphocytes. NLC gene expression patterns suggest their similarity to TAMs and differ between patients depending on ZAP70 protein expression status. NLC number in vitro corresponds with CD14 expressing cell count and beta-2-microglobulin serum level, and positively correlates with leukemic lymphocyte viability. As NLCs strongly express genes for adhesion molecules and secrete chemokines of antiapoptotic activity, they should be considered as a target for anti-microenvironment therapy of this incurable disease.

Significance of Polymorphisms and Expression of Enzyme-Encoding Genes Related to Glutathione in Hematopoietic Cancers and Solid Tumors

Antioxidant compounds such as glutathione and its enzymes have become the focus of attention of medical sciences. Glutathione, a specific tripeptide, is involved in many intercellular processes. The glutathione concentration is determined by the number of GAG repeats in gamma-glutamylcysteine synthetase. GAG polymorphisms are associated with an increased risk of schizophrenia, berylliosis, diabetes, lung cancer, and nasopharyngeal tumors. Cancer cells with high glutathione concentration are resistant to chemotherapy treatment. The oxidized form of glutathione is formed by glutathione peroxidases (GPXs). The changes in activity of GPX1, GPX2, and GPX3 isoforms may be associated with the development of cancers, for example, prostate cancer or even colon cancer. Detoxification of glutathione conjugates is possible due to activity of glutathione S-transferases (GSTs). Polymorphisms in GSTM1, GSTP1, and GSTO1 enzymes increase the risk of developing breast cancer and hepatocellular carcinoma. Gamma-glutamyl transpeptidases (GGTs) are responsible for glutathione degradation. Increased activity of GGT correlates with adverse prognosis in patients with breast cancer. Studies on genes encoding glutathione enzymes are continued in order to determine the correlation between DNA polymorphisms in cancer patients.

Expression of circulating miRNAs associated with lymphocyte differentiation and activation in CLL—another piece in the puzzle

Expression of microRNAs is altered in cancer. Circulating miRNA level assessed in body fluids commonly reflects their expression in tumor cells. In leukemias, however, both leukemic and nonleukemic cells compose circulating miRNA expression profile of peripheral blood. The latter contribution to extracellular miRNA pool may result in specific microenvironmental signaling, which promotes proliferation and survival. In our study, we used qT-PCR to assay peripheral blood serum of 22 chronic lymphocytic leukemia (CLL) patients for the expression of 84 miRNAs associated with activation and differentiation of B and T lymphocytes. Results were analyzed regarding the most important prognostic factors. We have found that the general expression of examined miRNAs in CLL patients was lower as compared to healthy volunteers. Only miR-34a-5p, miR31-5p, miR-155-5p, miR-150-5p, miR-15a-3p, and miR-29a-3p were expressed on a higher level. Alterations of expression observed in CLL patients involved miRNAs associated both with B and T lymphocyte differentiation and activation. The most important discriminating factors for all functional miRNA groups were trisomy 12, CD38 expression, B2M level, WBC, and NOTCH1 gene mutation. Correlation of expression of miRNAs related to T lymphocytes with prognostic factors proves their supportive function in a leukemic microenvironment. Further studies utilizing a larger test group of patients may warrant the identification of circulating miRNAs that are key players in intercellular interactions and should be considered in the design of microenvironment-targeted therapies.

New boys in town: prognostic role of SF3B1, NOTCH1 and other cryptic alterations in chronic lymphocytic leukemia and how it works

Abstract B-cell chronic lymphocytic leukemia (B-CLL) is one of the most common leukemias of the elderly. To date, although many prognostic factors are known, none are universal or easily accessible thus allowing for the stratification of patients to slow-go and aggressive-course groups. Recent studies have identified new recurrent mutations in CLL cells, including mutation of the gene encoding one of the spliceosome subunits, SF3B1, mutation or rearrangement of NOTCH1, a gene of well-known tumorigenesis association, and disruption of BIRC3, a member of the inhibitors of apoptosis (IAP) family. This article presents the current state-of-the-art findings concerning the prognostic significance of these new alterations, as well as an explanation of the mechanisms underlying their biological impact on CLL lymphocytes.

The incidence of breast cancer in population of young women from Podkarpackie province in 2002–2011

Introduction Breast cancer (BC) in young women of Podkarpackie province accounts for approximately 11.0% of all diagnosed breast tumors. Aim of the study Aim of the study was to assess the trends in incidence of BC among women younger than 44 from Podkarpackie in the years 2002–2011. Material and methods 614 cases of malignant BC and 26 cases of cancer in situ were analyzed. The crude and the standardized incidence ratios were estimated; the percentage of histopathologically confirmed cancer cases and the percentage share of registered malignant breast tumors were calculated. The analysis of incidence in individual counties was also presented, as well as the stages of clinical advancement at diagnosis and the methods of treatment. Results The number of registered cases at 2011 was 73, and it was 37.7% higher as compared to 2002. During the period analyzed, the increase in the crude and the standardized cancer incidence ratios was observed. The percentage share of BC in the examined group increased of 5.4% in 2011. Significant variation in incidence among different counties was observed. The incidence ratios ranged from 65.8 to 93.1/100 000. BC in young women most commonly was diagnosed as locally advanced and over 70% of patients were radically treated. Conclusions Even though the progress in diagnostics and treatment has been made, BC in young women is diagnosed later than it should be and at considerably advanced stage. It is relevant to propagate the knowledge among women and health professionals to emphasize that BC may affect young women.

Association between rs7901695 and rs7903146 polymorphisms of the TCF7L2 gene and gestational diabetes in the population of Southern Poland

OBJECTIVES The etiology of gestational diabetes mellitus (GDM) remains to be fully elucidated. Elevated risk for type 2 diabetes in patients with history of GDM and for GDM in women with familial history of diabetes may suggest that GDM and type 2 diabetes share a common genetic and environmental background. The TCF7L2 (Transcription Factor 7 Like 2) gene is one of the most important genetic factors of the established correlation with type 2 diabetes, and it may also play a role in the pathophysiology of GDM. The aim of the study was to assess the influence of two polymorphisms of the TCF7L2 gene (rs7901695 and rs7903146), which are associated with the development of type 2 diabetes, in women with GDM. MATERIAL AND METHODS The study included 50 women with glucose tolerance disorders diagnosed for the first time during the current pregnancy. Single nucleotide polymorphisms (SNPs) were genotyped using allelic discrimination. The results were confirmed using the sequencing method. Selected clinical parameters were also analyzed. RESULTS No correlation between the studied polymorphisms of the TCF7L2 gene and GDM was observed. Glycemic control with diet or diet and insulin was associated with better control of the weight gain during pregnancy. CONCLUSIONS No correlation between rs7903146 and rs7901695 polymorphisms of the TCF7L2 gene and GDM was found. Glycemic control with diet or diet and insulin is associated with better control of the weight gain during pregnancy.

Molecular Diagnostics of Acute Myeloblastic Leukemia

Acute myeloblastic leukemia (AML) is a genetically heterogeneous disorder. In approximately 60 % of cases specific recurrent chromosomal aberrations can be identified by modern cytogenetic methods, which enable risk stratification. In these AML subgroups, molecular diagnostics serve as an additional tool to confirm and complement cytogenetic data. In the remaining 40 % of AML cases, with normal karyotype (NK), as well as in core binding factor leukemias (CBF-AMLs), molecular techniques enable the identification of intragenic aberrations and gene expression markers, which further differentiate prognosis of AML. In addition to molecular risk stratification established at the moment of diagnosis, minimal residual disease (MRD) assessment by means of highly sensitive real-time quantitative polymerase chain reaction (RQ-PCR) provides a basis for therapeutic decisions in the course of disease.

Distinct molecular subtypes of gastric cancer: from Laurén to molecular pathology

In Western countries the majority of gastric cancers (GC) are usually diagnosed in advanced stages reporting a 5-year survival rate of only 26%. The Laurén classification of GC was most widely used in clinical practice since it reflects GC morphology, epidemiology, tumor biology, clinical management and outcome. Despite the initial promise of individualizing antitumor treatment, the management of GC still remains relatively broad and general. Apart from clinical staging, molecular profiling enables targeting of the identified underlying alterations, rather than histology. In contrast to breast carcinoma, molecular classification of GC does not yet imply treatment modality. Molecular classifications of GC and their therapeutic implications are therefore extensively studied. The current proposed molecular divisions of GC come from three different parts of the world where different standard treatment modalities for advanced GC are recommended. Wider use of GC molecular subtyping may solve problems, such as susceptibility to novel systemic therapy regimens or selection of patients for aggressive surgery and targeted adjuvant/conversion therapy. In any case, the rapid entry of novel molecular targeted therapies into routine oncology practice clearly underscores the urgent need for clinicians to be aware of these new possibilities.

Detection of chromosomal changes in chronic lymphocytic leukemia using classical cytogenetic methods and FISH: application of rich mitogen mixtures for lymphocyte cultures.

One of the research methods of prognostic value in chronic lymphocytic leukemia (CLL) is cytogenetic analysis. This method requires the presence of appropriate B-cell mitogens in cultures in order to obtain a high mitotic index. The aim of our research was to determine the most effective methods of in vitro B-cell stimulation to maximize the number of metaphases from peripheral blood cells of patients with CLL for classical cytogenetic examination, and then to correlate the results with those obtained using fluorescence in situ hybridization (FISH). The study group involved 50 consecutive patients with CLL. Cell cultures were maintained with the basic composition of culture medium and addition of respective stimulators. We used the following stimulators: Pokeweed Mitogen (PWM), 12-O-tetradecanoylphorbol 13-acetate (TPA), ionophore, lipopolysaccharide (LPS), and CpG-oligonucleotide DSP30. We received the highest mitotic index when using the mixture of PWM+TPA+I+DSP30. With classical cytogenetic tests using banding techniques, numerical and structural aberrations of chromosomes were detected in 46 patients, and no change was found in only four patients. Test results clearly confirmed the legitimacy of using cell cultures enriched with the mixture of cell stimulators and combining classical cytogenetic techniques with the FISH technique in later patient diagnosing.

Examination of the FLT3 and NPM1 mutational status in patients with acute myeloid leukemia from southeastern Poland

Introduction Acute myeloid leukemia (AML) is a genetically heterogeneous disease at both the cytogenetic and molecular levels. In AML cells many chromosomal aberrations are observed, some of them being characteristic of a particular subtype of patients, and others being less significant. Besides chromosomal abnormalities, the leukemic cells can have a variety of mutations involving individual genes. The aim of this work was to investigate the frequencies of molecular alterations with the focus on FLT3-ITD and NPM1 mutations in AML patients of different age groups living in a southeastern region of Poland. Material and methods The study group comprised 50 consecutive AML patients. We analyzed bone marrow samples by conventional cytogenetics. Cytogenetic evaluation in selected cases was complemented by the FISH technique. The internal tandem mutation in the FLT3 gene was identified using polymerase chain reaction (PCR), and the NPM1 mutation was assessed by direct nucleotide sequencing. Results The studies using classical cytogenetics showed chromosomal aberrations in 32 (64%) patients. In 18 cases no changes in the karyotype were found by conventional karyotyping. FLT3-ITD mutation was detected in 4 (8%) patients and mutation of NPM1 in 3 patients with AML (6%). Conclusions The incidence of both mutations in our study group was lower than described elsewhere. We have confirmed that FLT3-ITD occurred more commonly in older patients and it was associated with shorter overall survival. By contrast, mutation of exon 12 of the NPM1 gene seems to be a good prognostic factor in AML patients with normal karyotype.